1. Field of the Invention
The present invention relates to an arrangement for detecting and initiating indication of doses of radiation, which can be constituted of ionizing radiation (X-radiation, α- and β-radiation, etc. Advantageously, the arrangement and the meter can also be utilised for measuring radon and solar radiation, and other (dangerous) radiation to which the human body is exposed. The arrangement and the meter, respectively, include radiation receiving means and function handling means for storing and displaying received radiations/radiation doses. Thereby, the means are operable by means of one or several power sources.
2. Description of the Related Art
There is a need of individual meters which can directly warn the user at certain radiation levels and record accumulated doses over time (days, months, years). Today, a number of so called active (battery operated) meter alternatives are available in the market, wherein some are known since about 15 years. The known meters are designed with relatively large external dimensions which are oriented towards science and consume far too much electrical power to be used during a long succession of years without requiring battery change. It is also previously known with so called passive individual dosimeters (non-battery operated) which are used for recording accumulated dose.
There is a need of an integrated individual dosimeter which is small (having a so called thumb-volume) and can be used for at least 5 years with the same non-rechargeable battery. There is also a need of a smaller meter (having a thumb nail-volume) which measures and warns of dangerous radiation and which is intended for measuring substantially shorter time periods. Furthermore, the meter should be resistant to environments which are mechanically difficult, temperature-variable and humid. It should be easily readable with respect to accumulated dose and time-stored values (even values up to about 100 dose values). There is also a need to be able to stimulate and facilitate the desire of ordinary people to utilise the relevant meters. The smallness is of critical importance for easy and natural use of the meter. The use of an internal battery with remarkably small external dimensions contributes to this smallness, and all without having to sacrifice a reliable and clear-cut function. The object of the present invention is to solve these problems entirely or partially.